it’s adaptable by design.
No. No it is not. It was never designed. There is no design. It is adaptable by practice or usage (sadly, in many cases such as…)
something that built off of this idea
So, this something was something that was not built ON this idea, because you are clearly stating that it was built elsewhere other than ON this idea - namely OFF OF this idea.
See? Your usage has adapted the language to a new usage where what you THINK it means may hold true informally by repeated usage, but in fact means quite the opposite.
Metaphorical usage may hide the idiocy of this so let’s try a non metaphorical usage.
The brick walls were built on the foundations. Good. That is exactly where they should be. But if the brick walls were built off of the foundations (as you would no doubt say they were) I, for one, would not buy that house for love nor money. I don’t want my brick walls built on who knows what, elsewhere (i.e. off of) than on the foundations, thank you.
Another skirmish in the American War on Prepositions (and other abstract nouns, like drugs and terror).
But yes, typesetters have much to do with it, as does it being a highly composite language (esp. re Norman and Anglo-Saxon colliding only a thousand years ago.)
